code: def testPickleSharding(self):
      sharding = pxla.ShardingSpec(
          (pxla.NoSharding(), pxla.Chunked((2, 2)), pxla.Unstacked(3)),
          (
              pxla.ShardedAxis(0),
              pxla.ShardedAxis(1),
              pxla.ShardedAxis(2),
              pxla.Replicated(4),
          ),
      )
      self.assertEqual(pickle.loads(pickle.dumps(sharding)), sharding)
  
imports: import pickle
  import unittest
  from absl.testing import absltest
  from absl.testing import parameterized
  import jax
  from jax import numpy
  from jax import config
  from jax.interpreters import pxla
  from jax._src import test_util
  from jax._src.lib import xla_client
  import numpy
label_desc: Use image node_id 7 for calling the PickleTest obj's underlying member method code with example usage: obj.testPickleSharding() without return types